The stone face, in the middle of the frame w/ the lines.
http://cloud.steampowered.com/ugc/559812102321377783/9B64B673843C23F1B0DA6472716517F223B4EFE2/
Same shot. A little closer wo/ the lines.
http://cloud.steampowered.com/ugc/559812102321362797/3523817B8EC2F87DAD35A7BFDD8C5D5EC5745D27/
I have been running on Ultra settings. Now that I am implementing mods, I need to back off to High settings. Doing so causes the almost vertical gray lines to appear. I can change the settings back to Ultra, and the are gone.
I remember a member correcting this with an adjustment to an ini file. (I think) I can't remember what forum or topic. I tried to search, but to no avail.

It should be in your SkyrimPrefs.ini, the one located in your My Documents\My Games\Skyrim folder. Should be under the [Display] section, near the end. Mine looks like this (complete with tweaked ShadowBiasScale setting):
